If you have one of the old designed hand controls that goes into a junction box you will need to use item "A2" in the diagram. The new hand control plugs directly into the motor and the control box is no longer used. The power supply also plugs directly into the motor at a 2 pin capped connector that was not used before.

If your seat lift only works in one direction or not at all the hand control is a good place to start. We have found that if all the connections are tight going from the hand control to the motor and your back lighted remote is lit then you have a 75% chance of having a defective hand control. It is also not a bad idea to have a backup chair lift hand control because when it does go when your in the relined position it can make it very difficult to get out of the lift chair.